High-Voltage Transmission for Wind
Moving Forward in Kansas, Oklahoma

Dec 15, 2008 - Wind Energy Weekly

Two high-voltage transmission lines
that could integrate up to 5,800 MW of wind power
took a significant step forward recently with approval
of the projects’ transmission rate incentives by the
Federal Energy Regulatory Commission.

The two projects, known as Tallgrass
and Prairie Wind, include 400 miles of 765-kV transmission
lines crossing Southern Kansas and the Oklahoma panhandle.
The lines will become operational in 2013 if remaining
permits are granted and cost allocation agreements
reached according to plan.

The two projects will operate within
the footprint of the Southwest Power Pool (SPP), the
regional transmission organization for the Southern
Plains. There are currently more than 40,000 MW of
wind projects seeking interconnection to the grid
in this region. SPP has taken a lead role in reforming
the way transmission is planned and paid for to better
facilitate the construction of transmission used in
integrating wind projects.

The Prairie Wind and Tallgrass projects
would become the highest-voltage transmission lines
to operate west of the Mississippi River. Currently,
more than 2,100 miles of 765-kV transmission is operational
in Ohio, Indiana, Kentucky, West Virginia, and Virginia,
although most of the U.S. grid operates at voltages
of 500-kV and below.

There are significant cost and efficiency
advantages to building transmission lines at higher
voltages. In fact, a 765-kV line can carry as much
electricity as six 345-kV lines, at 1/3rd the cost,
using 1/4th as much land, and with 1/10th the line
losses.

A recent analysis by the consulting
firm Charles River Associates International found
that a high-voltage transmission network in the SPP
region, of which the Prairie Wind and Tallgrass lines
are the first phase, would generate significant benefits
for the region. According to the study, the project
would yield savings of around $1 billion per year,
more than twice the $400-500 million annual cost of
the transmission investment. The new transmission
infrastructure could bring 14,000 MW of new wind plants
online, reducing carbon dioxide emissions by 30 million
tons per year. The transmission project, combined
with the associated wind farm development, would also
create 10,000 construction jobs and 5,000 new permanent
jobs, $60 million in annual property tax revenue,
and $500 million in economic activity each year.

The Tallgrass project is a joint venture
between OGE Transmission, LLC, and Electric Transmission
America, which is a joint venture between AEP Transmission
and MidAmerican Energy. Prairie Wind is a joint venture
between Westar Energy and Electric Transmission America.